i would warn that this technology as you implied is something that is very well-known in domestic circles as well on a variety of websites. although we commonly see it in the al qaeda world, we don't think it's distinctive enough to draw conclusions at this point. >> do you get the impression that the person who made this bomb is trying to cover their tracks? meaning this is not somebody looking for attention, but covering their tracks because they want to do it again or covering their tracks for another reason that they are trying to stay in hiding? >> i think so. i think the lack of a plan of responsibility from outside the u.s. and international terrorist groups or at least of lack of a credible claim starts to make one suspect more and more as hours and days pass that this was an individual or a group operating solely here in the united states. that doesn't tell you if it's anti-government and a domestic group and inspired by al qaeda, but as time goes on, a lack of a plan of responsibility from overseas, you do have to look more within the united states. >> in your experience, what s